Copy and paste a pose onto a different character
Assuming the bones have the same names :

Select the first armature. In Pose mode, select all bones. In the Dope Sheet, select all the keys, Ctrl+C.

Select the second armature, pose mode, select all bones. Add a keyframe on the same channels used in the first pose (like LocRot or LocRotScale). In the Dope sheet, Ctrl+V.